When women with lung disease quit smoking, their lung function improves more rapidly than that of men in the same situation. Cigarette smoking is a major cause of chronic pulmonary obstructive disease (COPD), the fourth most common cause of death in the USA. It involves damage to lung tissue which causes increasing breathlessness and fatigue.

 Researchers for the Lung Health Study in the USA have studied more than 5,300 middle-aged smokers for five years. All had mild or moderate COPD. In the first year after quitting, those who did had improved lung function. Women did better than men, at least initially, although the gap between the sexes did narrow over time. Those who continued to smoke experienced a decline in lung function that was more or less the same for men and women.

Source

American Journal of Epidemiology 1st June 2003